Fuel pump for internal-combustion engines



P. LORANGE FUEL PUMP FOR INTERNAL COMBUSTION ENGINES Filed Sept. 21. 1927 Patented Dec. 17, 1929 UNITED sures PATENT OFFICE PROSER LORANGE, OF MANNHEM, GERMNY FUEL PUMP FOR INTEBNAL-COMBUSTION ENGINES Application filed Septexhber 21, 1927, Serial No. 220,986, and in Germany September 22, 1926.

. The fuel supply to internal-combustion ngines of the Diesel type is generally re'gulated V .by'means of separate valves or slides' the control of which involves complicated structures which are of considerable resistance to the governor.

The object of the present invention is to produce a simple and easily operated fuel control, and the invention consists in furnishing tl 1e fuel pump with a hollow rotatable piston} which is guided in a sleeve and provided with a lateral aperture which is normally cldsed by said sleeve and which is uncovered at the end of the pressure stroke for setting the compression chamber into communication with the suction pipe through the piston and interrupting the feed, the sleeve being provided 'With a helically inclined edge so as to allow the uncovering of the aperture 5 to be advanced and retarded by a rotary adjustment of the piston.

The fuel is preferably fed through the piston to the compression space, the piston being adapted to carry the suction valve.

Fig. 1 of the aecompanying drawings represents part sections of the piston and guide sleeve and of the sleeve alone, the piston being shown in its simplest construction.

F 2, a longitudinal section of a pump according to the invention, fitted with a piston of modified construction, 7

Fig. 3, a cross-section on the line 33 of Fig.2, and

Fig. 4, a cross-section 1 theline l-4 of Fig. V

The pump piston B of the fuel pump of an internal-combustion engine of the Diesel type, is made hollow and provided with a lat eral aperture z through which the compression space ont the pump can be set into communication with the suction pipe through the piston for inter'rupting the.feed of fuel. The piston is guided in a sleeve A whereby the aperture z" 1s normally covered, the interruption of the feed being determined by the position of the ed e of the sleeve relative to the 'path in whic the aperture is moved. The edge of the sleeve is helically incl1ned, and the piston is rotatable so that the uncovering of the aperture a can be advanced and retarded te suit the load on the engine by a rotary adjmtment of the piston.

Fig. 2 shows a complete pump construction according to the invention.

The pump casing 0 is supported by means of an adjustable nut Q on a frame R and guides in its lower end a springpressed pump actuating member 0 which beairs by means of a roller M against the pump operating cam N. The sleeve A in which the pump piston B is guided is'supported on a shoulder in the upper part of the casing and held in position by a valve sleeve D, a headed nipple G to which the compression pipe J is connected, and a nut H which closes the upper end of the pump casing. The suction pipe K communicates throughfthe side of the pump casing with a duct fin the sleeve A and the pis ton has a wide peripheral groove through which and through apertures 76 the duct f 7 ommunicates with the interior of the hollow pump piston. The upper end of the latter forms, inthe construction according to Fig. 2,

a seat for the suction valve B. The valve sleeve D is recessed to form a compression space above the guide sleeve A and is formed with a seat for the compression valve F. The casing C is out open to admit a lever arm L connected to a boss which is held rotatably between the end of the sleeve A and the lower 80 part of the casing C. The tail endof the piston B is flattened, as shown in Fig. 4, and passes.through a corresponding aperture in the boss of the lever L so that the piston is compelled to participate in the rotary adjust- 35 ment of the boss. The piston is coupled to the actuating member O by means of two diametrically opposite lugs P which are admitted through a keyhole aperture into an undercut recess in the end of the actuating member. In the normal position of-the arm L (the position L in Fig. 3) the lugs P are at 90 to the entrance position and allow the arm to be turnedthrough 45 in either direction (positions L and L without severing the. connectionbetween the piston and the actuating member. When the lever is turned 90 from the normal position (position L or" diametrically opposite) the piston is free'a'nd can be withdrawn axially from the casing.

after the removal of the nt H and the sleeve D. 2

When the piston descends, the valve E opens to admit the fuel into the compress on space. On the commencement of the upvvard stroke of the piston, the valve E is closedg and the valve F is thrust open,and, fuel Wiil oe fed through the pipe J into the engine cylinder. As soon as the aperture z 1s uncovered by the edge of the s1eeve A, com V munication will be established through the piston between the compression spaceand the suction pipe K, and the feed 05E fuel Will ne interrupted. As the edge of the sleeve A is helically inclined, the uncovering of the aperture i can, by a rotar displaoementdf the piston, be efiected at difierent points of the pressure stroke, and the duration of the feed can thus be regulated to meet the -ioad on the.engine.

VVhen the upper end of the piston is elosed, as shown in Fig. 1, the pump must be provided with the'ordinary valvearrangement.

I daim: 1. A fuel pun1p inder, having a compression space and an out- Iet passage leadingf rom *said spaee, a de 1ivepy valve in said passage, a reoiprocating piston arrang&ad in the cylinder coaxiaHy with said valve and formed with an axial bore which communicates with the comptession space, a suction valve seated in the orifice of the piston bore so as to close the communicatiqn normally', an inlet pipe comniunicating permanenfly with the piston bore, a

guide s1eeve for the piston arranged in the cylinder and formed with a helically ont end which confines the compression space in the neighbourhood of the piston, the piston being provided with a lateral aperture arranged so as to be normally closed by the guide sleeve and uncovered b the helical end of the latter at the end of t e compression stroke so as to relieve the pressure-through the piston bore and inlet pipe, and means for adjusting the piston about its axis so as to vary the angular position of the lateral aperture relative to the helical end of the guide sleeve.

2. ihe structure claimed in claim 1 in combmatmn wlth' an actuating. member for the piston, and lugs on the piston whereby the latter is coupled to the actuating member so as to allow relatrve rotary dis lacement, piston and 1ug being admitted tirough a keyhole aperture into engagement with the atuating member. PROSPER LORANGE.

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for internal-ccmbustion. engines of the Diesel-type, comprising a cyl- 

